Notes & Queries 09/28/09

byPaul GilsteronSeptember 28, 2009

Modeling a Space-Based Future

The submission deadline for the MiniSpaceWorld contest has, according to Tibor Pacher, been extended to November 1. Those with a yen to build scale models with a space theme should be considering the possibilities in the project, an exhibit showcasing everything from current rocket technology to basic principles of physics and astronomy, space travel as seen in science fiction and more. MiniSpaceWorld draws on the inspiration of the Miniatur Wunderland in Hamburg, which does for model railroads what Pacher hopes to do for space-themed modelers and educators.

Image: Tibor Pacher, who leads the MSW effort.

With the help of the Roland Eötvös Physical Society, the MSW design particulars are now being circulated to 1500 secondary school physics teachers in Hungary, which is the reason for the deadline extension. Full particulars can be found on the site, where I notice that the design contest award ceremony will be held in Budapest on December 5. The Hamburg railroad venue has shown, by drawing over five million visitors since its opening, that high quality modeling will have an audience. From model railroads to space may not be that big a leap.

Two Takes on Exotic Physics

Next Big Future recently hosted the Carnival of Space, always a good read, but I want to point you in particular to Brian Wang’s own posts on the Mach Effect and the work of James Woodward. Brian interviews physicist Paul March on his work on thruster applications growing out of these ideas in two posts that you can find here and here. At stake, March believes, is a drive that “…requires a certain minimum amount of local reaction mass to work with, which interacts with the mostly distant mass/energy in the universe via the ambient cosmological gravinertial field wave interactions.”

Interactions with the distant universe? To get to the heart of this, we have to go back to Ernst Mach, who explained inertia as being causally related to the most distant matter in the universe, an idea that is, needless to say, controversial. Einstein tried, but failed, to work the notion into his developing ideas of General Relativity, but the question of inertia’s origin remains tantalizingly elusive.

Image: James Woodward (California State University, Fullerton).

Woodward has been examining what he believes to be transient mass fluctuations in accelerated masses that could be explained in a Machian framework. It’s interesting stuff, and the subject of experimental work that is ongoing, although whether we are dealing with actual effects or ‘noise’ in the data is still unclear. Woodward’s own Web site gives his take on the matter. We also looked at Woodward’s work in our Frontiers of Propulsion Science book.

Interestingly, one reader (writing under the name Kurt9, familiar to Centauri Dreams regulars) noted on Brian’s site that Woodward’s notions seemed similar to John Cramer’s ideas on retro-causality, which are based on his transactional interpretation of quantum mechanics. March, in fielding the question, notes that Cramer’s concept is important because “… it provides a ready-made explanation of how inertial momenergy waves propagate to/from the mostly distant mass/energy in the universe in apparently zero local time.” We continue to await the results of Cramer’s lab work, a widely anticipated experiment that we’ve discussed often in these pages (an early post on the subject is here).

Cramer, by the way, investigated some of Woodward’s concepts in a study sponsored by NASA’s now defunct Breakthrough Propulsion Physics project. There are plenty of interesting links to follow in Brian’s two articles. Adam Crowl also discusses Woodward this week.

Let me also point you, while we’re talking about exotic physics, to Richard Oboussy’s interview with Jose Natario on his Interstellar Journey site. Natario has written two influential papers on warp drive. Quoting the physicist:

…I set up a fairly general model for a warp drive spacetime, which includes the Alcubierre model as a particular case. I showed that it is possible to have models where there is no overall contraction or expansion of space (although space does get severely distorted on the warp bubble wall). My hope was that one would then get less severe violations of the energy conditions, but that turned out not to be the case: one can easily prove that these models always violate the positivity of energy. I also showed that there are two other (in my view more serious) problems with the warp drive concept, namely the existence of horizons and infinite blueshift regions.

A major problem with current warp drive concepts: The warp ‘bubble wall’ is disconnected from the interior of the craft, making it impossible for crewmembers inside the vessel to control the wall. How to control something moving faster than light from inside the bubble itself, when your signals, traveling only at the speed of light, cannot reach the front of the bubble wall?

Interstellar theorists are always looking for ways to reduce mission times enough that a scientist working on the project would live to see its completion. For Alpha Centauri, that means about ten percent of lightspeed, given the lengthy times assumed to develop and build the craft in the first place. But another way around the problem is to lengthen human lifespans to the point where a crew could survive a centuries-long mission, explore, and live to make the return.

Although we don’t often get into life extension issues here, it’s interesting that Athena Andreadis (University of Massachusetts) finds one current long-life motif to be all but pointless. Calorie reduction is said to make us live longer, but does it? Check this out, from her recent article in H+ Magazine:

All vitamins except B and C are lipid-soluble. If we don’t have enough fat, our body can’t absorb them. So the excess ends up in odd places where it may in fact be toxic –- hence the orange carotenoid-induced tint that is a common telltale sign of many caloric restriction devotees. Furthermore, if we have inadequate body fat, not only are we infertile, infection-prone and slow to heal due to lack of necessary hormones and cholesterol; our homeostatic mechanisms (such as temperature regulation) also flag. And because caloric restriction forces the body to use up muscle protein and leaches bones of minerals, practitioners can end up with weakened hearts and bone fractures.

Not only that, but because the brain runs on glucose, it starts releasing stress chemicals when it’s not getting what it needs, a problem that can induce hallucinations or false euphoria. Thus the history of shamans, desert prophets and others who have undertaken fasting as part of a quest for visions. And if you’re counting on red wine to keep you ticking now that you’ve learned you can eat again, Athena doesn’t think much of resveratrol as a life-extender:

…it doesn’t even extend life in mice –- so the longer lives of the red-wine loving French result from other causes, almost certainly including their less sedentary habits and their universal and sane health coverage. That won’t stop ambitious entrepreneurs from setting up startups that test sirtuin activators and their ilk, but I predict they will be as effective as leptin and its relatives were for non-genetic obesity.

Andreadis, noting that human lifespan has nearly tripled thanks to vaccines, antibiotics and other factors, doubts we will be able to extend it much further. Moderately overweight people are, according to recent studies, the longest-lived. Maybe propulsion scientists are our best bet after all, at least until we come up with an anti-aging technique that at present seems to be off the charts.

For life extension, SENS is the proper approach. I take resveratrol, among other things, and have noticed subtle positive effects. However, I don’t believe for a second that it will extend my maximum life span. I see the stuff I take as a stop-gap to get me to when SENS and stem cell regeneration are available (2040?). Otherwise, its the cryonics dewer for me and I would really prefer not to have to do this.

SENS and techniques like it are the only game in town for the near future. Later on, synthetic biology and redesign of the metabolic pathway will also be done (but I see this as post 2050 stuff).

TThere is Woodward and March’s ideas with regards to Mach’s Principle and then there are Haisch, Davis, and Puthoff with their ideas about quantum vacuum fluctuations (QVF).

The Mach and QVF stuff is interesting because these appear to be the only two known plausible explanation for inertia. Either one of them being correct should give us a space drive (but not necessarily an FTL). Paul March thinks MLT’s will give us a space drive (as well as completely change transportation here on Earth) but that further work with QVF and other areas will be necessary to get the FTL, if it’s possible.

Then there’s Heim Theory. Droescher and Hauser have published their latest paper:

The materials issue for Mach is the development of the dielectric material and the issue for Heim is the development of the high current capacity superconductor. At least to do the experiments to see if any of this is possible.

Arthur Clarke’s notes from his later novel The Songs of Distant Earth outlined his misgivings about warp drive and FTL speeds. He conservatively believed that vacuum energy could get very large vessels up to several percent of c while the crew were in hibernaculae. Interstellar voyages would be decades to centuries long. The hibernaculum is rarely mentioned these days, though it was thought out as a resource-saving measure in the Jupiter voyage in 2001: A Space Odyssey. What research has been done with induced hibernation? Is it feasible or unlikely?

Paul: “…whether we are dealing with actual effects or ‘noise’ in the data is still unclear. ”

I would argue, if it’s unclear then, statistically speaking, it is noise. What little I’ve perused in the past about Woodward’s work is consistent with a conclusion that it’s just noise. The only attempts to make a conclusion that there is a signal present appear to suffer from selection bias. In methodology and claims this subject bears much resemblance to Podkletnov’s anti-gravity experiments (which NASA also toyed with briefly).

Einstein, who was initially receptive to Mach’s ideas (an excellent review of Einstein’s thinking process is in Pais’ “Subtle Is The Lord”), discarded this cosmological view since it was an unnecessary assumption in the working version of general relativity. That is, it added nothing but it did constrain the universality of the theory (no preferred reference frame) with respect to cosmological models. It does not mean that Mach was wrong, just that the concept was not useful in that context.

Athena: “All vitamins except B and C are lipid-soluble. If we don’t have enough fat, our body can’t absorb them. So the excess ends up in odd places where it may in fact be toxic…”

Is this due to low body fat or only low calorie diets? This isn’t relevant to the blog’s theme, but I am curious since body fat measures and so forth are an interest of mine. For example, I maintain a high caloric intake combined with exceptionally low body fat. This is due to a combination of genetics and a high level of physical activity. In other words, I’m not starving myself but I am exceptionally lean. Unfortunately, it seems this won’t serve me well on a mission to Alpha Centauri.

Clarke has always been conservative about the possibility of physics developments. Some of his stories feature propellant-less space drives, but no FTL. I think this assumption is reasonable for writing hard-SF, and Clarke’s stories were about as hard as they come. At this point, I were writing hard SF, I would have the space drive but no FTL or wormholes.

The stuff I would write would have technology similar to Reynold’s “Revelation Space” or Greg Bear’s “Moving Mars” (but without the funky physics that gets invented in the latter).

Since I am in the cryonics scene, as one might describe it as, I will tell you about the “hibernation” as depicted in SF like “2001”. Its a fantasy. Forget about it.

Freezing (or vitrification) causes too much damage for the “easy” hibernation as depicted in these SF stories. This damage can be reduced with better cryo-preservation techniques such as vitrification. However, prefect whole body vitrification is likely impossible for technical reasons which are too long to explain here. The best we can do is effective cryo-preservation of the brain with less effective preservation (more damage) of the other tissues of the body. This will help to reduce the necessary technologies and interventions necessary to bring people out at the other end. In any case, repair of people in cryo-preservation (regeneration and reanimation) will require a technology based on synthetic biology and advanced stem cell regeneration. I believe it can be done and that cryonics can work. But it will take 100 years or more AND the people in cryonics themselves will have to do much of the development work themselves (no one else is going to do this for us). The key hurtle to overcome in any suspension is to have sufficient neuro-preservation such that the above technologies can accomplish revival without having to resort to a molecular-level repair technology sufficient to rebuild neurons individually from the inside as well as to restore the dendritic connections between them. This is the difference between use of foreseeable biotechnologies like stem cells and synthetic biology (even whole body regeneration) and something more speculative like “Drexlerian” nanotechnology (which I remain very skeptical of).

Fortunately for us, stem cell regeneration and synthetic biology are two of the fastest growing fields in the world right now. The reason why I think cryonics can work (IF we develop effective neuro-preservation of at least the brain) is that we or our future counter parts 100 years from now will be taking such off the shelf medical and industrial regeneration and synthetic biology and modifying it for our purpose of reanimating our friends who are in suspension. It is this last part that we will be doing ourselves. I, at least, do not expect anyone else in society to do it or even to have the slightest interest in doing such.

This brings me to my other point, which is when I get people making stupid comments like why would anyone want to do cryonics because no one in the future would want to bring you back. My flippant response to this is to say that this issue is totally irrelevant because we (either those of us who make it without having to be frozen or future members) will be doing the reanimation. We have no expectation of relying on the efforts of “outsiders” anymore than the Pilgrims or Mormons relied on “outsiders” to accomplish their objectives.

Andreadis may be right in the short and medium term about the chances for life extension much beyond the current four-score years, but I’d be willing to wager a small amount that there are people alive today who will live to see the year 2150 and perhaps even 2200.

I believe there will come a point (after thorny issues like heart disease, Alzheimers, and cancer have been knocked on the head) when the full force of the biomedical community will be ranged against the forces of entropy and decay that attack the human body. Viable solutions are just too far off at the moment for most people to pay much heed to the idea of living well beyond 100 years old, but I suspect that as soon as medical technology brings us within reach of such a goal, whether it be through nanobot cell repair or even cryogenics (as a stop gap) then there will be ample enough billions of dollars ready and waiting to invest in life extension. The profit potential would be almost unlimited for the first company to find a true life extending treatment.

Life-extension does raise some extremely thorny ethical issues. If enough people stop dying then Earth’s resources will be taxed even more than they are today, unless people also stopped having babies which leads to more ethical issues about the propagation of the species. But ethical or not, people will keep trying, and I believe they will eventually succeed perhaps within the next 50 – 100 years.

Even cryogenics raises some interesting issues. If you can reliably put someone into suspended animation for a decades, you might find there is a mad rush of people to put their lives on hold for 100 years or so in the hope that the future will bring them what the present has not — there are plenty of miserable people around out there. Certainly if you are diagnosed with a terminal illness then you have little to lose, if you have enough spare cash to keep you in cold storage until medical technology has advanced a little more.

I know someone who has a benign brain tumor that is slowly strangling her spinal cord. It’s in a very difficult place to operate on and the risks are very high that she might not survive an excision, so her best option is currently to hold on and hope that the medical technology and surgical techniques continue to advance to the point where the tumor is operable before it kills her. It’s a race against time where, if cyrogenics was a reality, it could help push her over the finish line.

Dear Paul, thank you for showcasing my H+ article! There will be more, and I encourage people to visit the site and leave footprints (good for the author’s morale!).

I very much want us to go to the stars in person, rather than by proxy — and during the day I do basic research in the molecular causes of dementia. So the issues of longevity and continuity of consciousness are in the forefront of my mind both literally and metaphorically! I discussed these topics extensively in my book, To Seek Out New Life, in my blog, and intend to continue doing so in at H+ as long as they’re willing to publish the articles!

I know all about cryogenics, SENS , nanobots… and the bottom line is: none of us here will live to have our lives extended by those technologies, whether we are signed up with Alcor or not. As for nanobots, they are already with us in the guise of enzymes and miRNAs. These, plus embryonic stem cells, are the way to go, although the fine-tuning will be long and excruciatingly hard — and the cultural/social/ecological problems arising from such interventions equally thorny.

This brings me to my other point, which is when I get people making stupid comments like why would anyone want to do cryonics because no one in the future would want to bring you back.

Actually, it would be just bad business sense not to do it. If companies stop reanimating earlier clients then nobody is going to trust them to reanimate future clients either. Even if other life extension technologies are available by then, I can see going into suspended animation continuing to be popular. For one, it’s a perfect way to time travel into the future.

Web search with ‘induced human hibernation’ yielded these articles from a few years ago:http://www.livescience.com/health/050421_hibernation.html April 2005
“We are, in essence, temporarily converting mice from warm-blooded to cold-blooded creatures, which is exactly the same thing that happens naturally when mammals hibernate,” said lead researcher Mark Roth of the Fred Hutchinson Cancer Research Center in Seattle. During the induced hibernation, cells virtually stopped working, reducing the rodents’ need for oxygen. “We think this may be a latent ability that all mammals have – potentially even humans – and we’re just harnessing it and turning it on and off, inducing a state of hibernation on demand,” Roth said.

http://www.space.com/scienceastronomy/scitues_hibernation_041012.html October 2004
“We’re providing some state-of-the-art, basic research on the field of hibernation,” said Marco Biggiogera, a hibernation researcher at Italy’s University of Pavia, adding that he and two colleagues, each from different Italian universities, are studying hibernation mechanisms for ESA.

I know all about cryogenics, SENS , nanobots… and the bottom line is: none of us here will live to have our lives extended by those technologies, whether we are signed up with Alcor or not.

Perhaps. But we’ll most certainly get radical life extension before we get any where near Alpha Centauri with anything more than a probe. Unless we get a Heim drive, I cannot see any scenario where we get into interstellar space prior to life extension. I actually think that the human expansion into space will never happen without radical life extension.

and the cultural/social/ecological problems arising from such interventions equally thorny.

I disagree. These are no more thorny than they were for any other invention we’ve made, like the car, airplane, or telephone. Culture and society always adapts to changing conditions and people who have, say, 500 year lifespans are going to have the more longer term focus that the “green” people are always ranting and raving about. The greens should be the biggest supporters of SENS and the like.

Also, people with vastly increased life spans will be a lot more interested and motivated to do space colonization (interstellar, O’neill, or both) than people with conventional life spans. The reason is that the long time horizons involved in this sort of thing requires people with equally long, if not longer personal time horizons. Its simply not going to happen any other way.

In any case “cultural/social/ecological” concerns are certainly no excuse to suppress development of radical life extension.

I also disagree about the cryonics. Yes, I am well-aware that they have not been attentive to some of the technical issues that they should have been (this has been a bone of contention over the years). I am also well-aware of some of the organization difficulties they have experienced over the years as well. However, some of them are now getting more focused in resolving many of the issues they should have do 15 years ago and the organizations seem to be doing a better job of getting their act together. Alcor seems to have a better board than it used to.

They are now working to resolve the “cracking” problem (KrioRuss is working on this as is CI) and Ben Best has done an impressive job of turning around CI since the retirement of Ettinger. Saul Kent, through 21st Century Medicine, has been funding and developing the neuro-vitrification that I mentioned previously. I have known the technical guys at 21cm for a long time. They are all solid guys and I have confidence in their abilities. If they can resolve both the cracking problem and develop effective vitrification of the brain (which I think they can), I think the “fidelity” of cryopreservation will be sufficient that you do stand a reasonable chance of making it out the other end. This is why I recommend cryonics even though some of you think it will not work.

Carl, this hibernation stuff will not work for long periods of time necessary for interstellar transport. This is being developed mainly to put people under for the 4-10 hours it takes to do specialized surgical techniques that would otherwise require use of a heart-lung machine.

Tacitus,

Cryonics will always be necessary, even after we cure aging. There will still be things that can kill us that the medical technology at that time will not be able to fix right away. In a post-mortal society, infectious agents (both natural and man-made) will still kill us. So can accidents and homicide. Many times, the technology to repair us will not exist, even in a post-mortal society. Cryonics is an ambulance ride into the future (medical time travel), when that capability will exist.

If I had to guess what breakthrough will enable us to travel to other solar systems, then I would guess that it will be a breakthrough in biochemistry rather than physics. How else is with me on this?

The fact that we have not been visited by an ET civilization could be due to any number of factors; however, if FTL is something that is possible and something that civilizations, after having reached a certain level of scientific/technical sophistication, are able to accomplish, then they would have the ability to quickly explore countless solar systems, probably including ours depending on their abundance/motivation. The fact that this visitation has not happened is not incompatible with the notion that FTL is possible, it just seems to me to reduce the likelihood of it being possible.

The rate at which we are learning more and more about chemistry and biology is astounding. DNA, the molecule our children learn about routinely in their high school biology classes, was unknown less than 70 years ago. Chemists estimate that even though millions of compounds have been synthesized to date, the fraction of chemical space still left to be explored is at least 99%. These facts lead me to believe that in a hundred yrs or so biochemists will figure out how to put human beings in suspended animation of indefinite length. This will be the key that opens up the Universe.

Clarke propelled the “Magellan” to 0.25c. The first seeder ships did ~0.02 c, eventually doing 0.2 c. There are a few errors in what Clarke wrote on various interstellar issues in that book, whether from creating an artificial tension (thus artfully misleading his readers) or from writing a novel at almost 70 years of age I’ll never know, sadly.

As for “hibernation” or “cryonic suspension” or whatever you want to call it, I suspect we will eventually be able to suspend life for indefinite periods, but it’ll require molecular level technologies we’re still in the very early days of. Would be nice if we could “dehydrate” ourselves like tardigrades and brine shrimp.

“Tardigrades are polyextremophiles and are able to survive in extreme environments that would kill almost any other animal. Some can survive temperatures of -273°C, close to absolute zero [4], temperatures as high as 151 °C (303 °F), 1,000 times more radiation than other animals such as humans[5], nearly a decade without water, and even the vacuum of space.[6]”

Spaceman: I think that the ability for us to take to space will come about from a combination of biological modifications and engineering advances. At the same time, recall that almost identical obstacles pertain to human “settlement” (loaded word) of the earth’s oceans.

Kurt9, I will make a general comment regarding predictions of what is possible. Perhaps because of the perceived position of biology in the science “totem pole”, it has been traditional for physicists, engineers, etc, to hold forth on biological issues at great length and with a great semblance of authority — often with such hilarious results as quantum microtubules. I discuss this puzzling assumption of expertise without specific qualifications here: On Being Bitten to Death by Ducks.

Despite my significant knowledge of physics (I was two courses short of a degree in that field), you will note that I don’t hold forth on the feasibility and technical aspects of Bussard ramjets, Alcubierre drives or solar sails, except to say that I would like to see faster alternatives to chemical drives. At the same time, I’m well aware that stable wormholes and faster-than-light drives will never materialize and that we’ll have to reconcile ourselves to the long slogs of arcships if we decide to launch crewed missions.

I’m a biologist who has explored large swathes of my discipline, in part because of my interest in space exploration. When I discuss an issue in my own field, it may contain wishes and projections, but the core conclusions are based on biological facts — not just what may become technologically possible, but what is intrinsically feasible. There are some biological limitations that we will never overcome, no matter how hard we wish or try. As for human adaptability, it is certainly astonishing. But it has also come at the price of near-exhaustion of terrestrial resources before we have attained the ability to access resources beyond earth.

The work of Jose Natario should be especially interesting for those commenters here on this website, who phantasize about faster-than-light travel again and again. Here — and in further articles available on the web — much evidence has been accumulated, that there is no way to conclude, that faster-than-light travel by warp drive could be possible. There is a plethora of problems: violations of the energy conditions, the crew inside the spaceship cannot control the warp bubble wall (great!), and — as only one example from a previous article — the crew would be bathed in deadly radiation, etc. etc.

By the way, there is a funny formulation: “I showed that it is possible to have models …”. Well, that’s entertainment ;-)

Kurt9, your link is to an armchair (i. e. non-peer reviewed) analysis by an emeritus computer scientist — which illustrates the point I made earlier about the assumption of expertise. Just because someone has time on their hands and ethernet access doesn’t make them either knowledgeable or right — particularly in topics outside their professional domain.

As for cryonics and the rest, I understand your wish not to appear duped and, of course, the fear of death haunts us all. However, ask yourself who is more objective: a scientist who is doing basic research (that is, without an explicit view to applications for profit) into causes of aging and dementia or someone who founded a company to make money from milking people’s fears by selling them the biotech equivalents of snake oil — whether these are telomerase “pills” that could turn cells cancerous to the tune of $15 K a year, or promises of resurrection at a steep rent by use of technology known to kill isolated cells in culture, let alone the intricate brain network.

There are some biological limitations that we will never overcome, no matter how hard we wish or try.

I find this a curious statement. When we talk about the possibility faster-than-light travel, it’s with the full understanding that there could be, and likely are, fundamental physical barriers that can never be overcome not matter how advanced our technology becomes. Contrast that with the possibility and hope that relativistic sub-light interstellar travel will be achievable one day. It will be insanely difficult, but there are no fundamental reasons why we won’t be capable of it some day in the distant future.

I see no reason not to equate the prospects of profound life-extension and suspended animation with those of relativistic sub-light travel–i.e. they will be extremely difficult to do, but there are no fundamental insurmountable barriers in our way.

I’m not rosy-eyed enough to believe that I will live long enough to benefit from either technology (another 40 years, with luck), but I am curious to know what fundamental biological limitations you believe will stop us from ever achieving these goals.

I would agree that there is no magic bullet waiting in the wings that will suddenly double our lifespan, but given what we have achieved in the very short number of years since the advent of bioengineering, it would seem very premature to think that we won’t one day begin to tackle and counter the ravages of aging-related cellular damage.

With suspended animation I can perhaps see that if it is proven that continuous electrical and chemical activity is absolutely required for the brain to survive (i.e. you can’t shut it down completely and start it up again and retain all higher level functions) then that might be an impossible barrier, but otherwise it seems mostly to be issues of complexity that need to be overcome.

I’m not belittling the difficulties of either task which is why I suspect that it will be many decades before we even get close to realistic solutions, but I just don’t see any reason for accepting such things will always be impossible.

Here is the corrected version of my post which had a big numerical error.

Regarding the above statement;

Interstellar theorists are always looking for ways to reduce mission times enough that a scientist working on the project would live to see its completion. For Alpha Centauri, that means about ten percent of lightspeed…”

10 percent of C would not be bad especially if we can augment human life expectancy to indefinite lifetimes. 0.1 C would enable us to travel one billion light-years not assuming the expansion of space time in 10 billion years background time. The radius of the observable universe should have about doubled in time, and so galaxies that are one billion light-years away now would probably be about 10 billion lightyears away 10 billion years from now. Given 20 billion more years, our space craft should be able to travel about 2 billion lightyears from the Milky Way not taking into count space time expansion.

One can imagine galaxy hopping huge world ships the settle a given super-cluster whereupon new world ships are built. Nuclear fusion could power nuclear reaction powered propulsion systems.

Since as a young boy, I have always enjoyed everything large, I am somewhat of an advocate of such world ships that could carry a population equal to the current global population wherein upon arriving at other galaxy super clusters, the world ships would send colonizing teams throughout the galaxy cluster, and things could jump start from there.

Such world ships could be electromagnetically insulated perhaps with multi-hulls made of cryogenic superconductors and the like for MW, RF, and IR containment. If the civilizations inside the ships could get by on 1,000 metric tons of fusion fuel per year by going ultra green and sustainable, a billion years would require only 1 trillion metric tons of fusion fuel. If the fuel was as dense as water, that would be the equivalent of a mere 10 kilometer wide cube.

No doubt such ships would be huge affairs, but perhaps as technology was refined much higher relativistic velocities could be reach perhaps even velocities commensurate with much greater than one multiples of gamma. I would imagine that matter antimatter fuel type reactions would be required here, or perhaps some yet to be discovered nuclear or sub-nuclear energy reaction that liberates much more energy per unit of rest mass than does ordinary low atomic number fusion reactions.

The general feeling among many of us space heads is that 0.1 C is doable although developing the requisite hardware and software required for controlled and safe flight at 0.1 C will take some doing.

Refining the VASIMR rocket can be a good initial step toward developing nuclear rockets with a fuel Isp of as much as 3 million, or expressed in terms of units of C, 0.119 C which is the quoted maximum fusion fuel Isp in Wikipedia. By the way, do not be afraid to consult Wikipedia, as some of their physics articles get very in depth with derivation of formulae. Some of the articles in Wikipedia are very sophisticated.

I think that a interplanetary human civilization eager to grow and expand during an era of peace and prosperity of indefinite duration would go for the development of 0.1 C and faster human crewed ships to other star systems with the goal of eventually going beyond our home galaxy.

Several proteins are now known to influence longevity, energy use and the response to caloric restriction, including sirtuins (thought to help the body ride out famines),receptors for insulin, IGF-1, and TOR (“target of rapamycin”) — an antimicrobial that was recently found to extend life span significantly, even when given to mice at an advanced…

However, ask yourself who is more objective: a scientist who is doing basic research (that is, without an explicit view to applications for profit) into causes of aging and dementia or someone who founded a company to make money from milking people’s fears by selling them the biotech equivalents of snake oil — whether these are telomerase “pills” that could turn cells cancerous to the tune of $15 K a year, or promises of resurrection at a steep rent by use of technology known to kill isolated cells in culture, let alone the intricate brain network.

You’re probably right about the telomerase treatment (I’ve never consider this, but then I consider the telomere theory of aging to be bogus). However, I have known the people involved in cryonics for over 20 years and, despite many of the problems that I mentioned previously, I can attest to the good character of those that I have worked personally with. I will also tell you that I have known the technical staff at 21cm for over 20 years as can attest to their character as well, as I can for Saul Kent and Bill Faloon. Cryonics may or may not work. Everyone I have dealt with in this milieu has always been up front about this being a speculative endeavor. Your suggestion that they are engaging in fraudulent activities is, quite frankly, libelous and offensive.

I’ve been following Cryonics closely for 10 years now I think since I first heard about it, both parties those for and against it have some valid points. Myself I like the idea that humans have a method for the first time in history (however slim and unlikely it would work now given current methods used) to beat information death. So here are our options now (assuming a “normal” death):

a) Get buried
b) Get cremated
c) Head neurosuspension or full body

a) and b) are a total loss, with c) at least some part of you is still around to witness whatever the future holds ;-)

For interstellar travel, why not just allow for having babies! The ship, if ever such a ship is built, will require engineering and knowledge of science that is in far excess of anything that we can muster now or even in a 100 years from now. So if we ever get to the stage where can build it, we could just build a really big ship, which will allow for multiple generations to live out their lives in persuit of a “new earth” or whatever desitination desired.

I feel the quest for eternal (or near eternal, i.e. more than 200 years) life is futile and its persuit just pain wrong. There is a sense of completion in death. We have our four score of years and that should be enough. A doubling of that, at the most, is about as much as we should think about persuing. There is nothing wrong with dying – it is our biological heritage.

Tacitus, the point you make about suspended animation (namely, that continuous electrochemical activity is required for the brain to retain most functions, not just higher ones) points to at least one absolute biological barrier equivalent to FTL. I said “some biological limitations” without going into detail. If anyone is curious, they can read my many articles on the subject either on my blog or at H+ magazine. To continue with the example you gave, mind uploading will never work because the mind is inseparable from the brain. Other problems (cancer, for example, and many genetic errors) will eventually be solved. So where is there a disagreement?

Kurt9, to give an informed opinion that someone is doing something that won’t have results is neither libelous nor offensive. As I said, you can continue hoping. The bottom line is that nobody frozen today will be resurrectable. The current technologies used for freezing don’t retain neuronal integrity.

Tesh, having children in spaceships is something that must happen for long-term viability. The issues are complex, from radiation to hybrid vigor, but we need to tackle them if we’re serious about long crewed space expeditions.

Larry, rapamycin is a poison — it suppresses the immune system. Also, whatever works in mice does not often work in humans. I wrote about both of these items in the first Eldorado Desperado article:

A little correction is due with regard to my previous post of the statement:

The radius of the observable universe should have about doubled in time, and so galaxies that are one billion light-years away now would probably be about 10 billion lightyears away 10 billion years from now.

The corrected statement is as follows:

The radius of the observable universe should have about doubled in time, and so galaxies that are one billion light-years away now would probably be about 2 billion lightyears away 10 billion years from now.

Galaxies that are 2.5 billion light years away currently should be about 5 billion light-yeas a away in 10 billion years, still very reachable by moderately relativistic space craft.

All this assumes that the universe doubles in size every ten billion years and thus that the the rate of expansion of a 1 billion light year interval of space in a given post inflation 10 billion year time step remains constant with respect to the rate of expansion of another 1 billion light year interval of space in a subsequent 10 billion year time step.

My hope is that the rate of the increase in the expansion of the universe that is evidenced by current observations, if such is indeed so occuring, will level off in the following few billion to few tens of billions of years, and that perhap the rate of expansion will be reduced over these time periods.

I strongly feel that even if the Special Relativistic Limit of C proves insurmountable, relativistic star flight will carry us out to distant galaxies and galaxies clusters.

However, given the consistency of the special relativistic physics that no energy or signal can travel faster than C through space, and that the whole ediface of modern high energy particle physics is based on the limit of C, I wonder if C might be a true limit nature imposes on us and our ETI friends in order to prevent issues of the integrity of causality. We might yet learn how to do superluninal travel, and so I encourage all of the readers of this post to keep the dream of such alive. I strongly feel that the book of FTL travel is far from closed.

Thanks for replying Athena. I will have to look into what cryogenics advocates say about suspending and restarting biochemical interactions.

To continue with the example you gave, mind uploading will never work because the mind is inseparable from the brain. Other problems (cancer, for example, and many genetic errors) will eventually be solved. So where is there a disagreement?

Well, here is one disagreement — that the mind is inseparable from the brain. While it may be insanely difficult, I don’t see why there would be a fundamental barrier that will never be overcome. The Silicon Age has barely reached 50 years old and we are already routinely producing chips with billions of transistors on them for a few dollars each, and storage devices in the trillions of bytes of information.

Again, I don’t see us being able to simulate anything close to the complexity of the human brain any time soon, but never? I would not be too sure, and I certainly don’t believe there is any metaphysical barrier to such a transfer. The mind is a artifact of the physical brain, nothing more.

Now, if you told me that being downloaded into an artificial brain running on silicon and software is not a particularly satisfying way of cheating death, I would tend to agree with you. Making a clone or a copy is just that, a clone or a copy. The only viable solution I could envision (which heaps more insane complexity upon complexity) would be for your original brain to be swapped out, piecemeal, while you are still alive, to make it a seamless transition. Then when your body gives out, your brain, your mind, is already in an easily portable and sustainable container and the sense of originality and uniqueness is maintained.

I feel the quest for eternal (or near eternal, i.e. more than 200 years) life is futile and its pursuit just pain wrong. There is a sense of completion in death. We have our four score of years and that should be enough. A doubling of that, at the most, is about as much as we should think about pursuing. There is nothing wrong with dying – it is our biological heritage.

Well, I’m sure that’s true for some, but given how ferociously many people fight the ravages of time, I doubt that’s the case for the wider population. There is a sense of completion about a lot of things, not just death. When someone retires, or quits their job to start a new one, or sees their kids leave home, or wins a World Series ring, and so on. The completion of one’s life is currently inevitable so it’s not surprising that there is such a sense of completion. It’s part of the coping mechanism, and it’s often the only way to bring an end to the suffering that people experience as they come close to death. Their bodies are tired and worn out, so it’s no wonder so many are ready to complete their lives.

But if you could live indefinitely as a fit and healthy young adult, I doubt anywhere near as many would see 80 years being anywhere near enough. I am sure there would be some who would never adjust to living far beyond the natural lifespan (many people commit suicide far younger than that when their lives become unbearable) but I suspect there will be more who will be grateful of the extra time they have been granted, and eventually the human race as a whole would adjust to their new lifespan.

Finally, it’s pretty much our biological heritage to die by the age of 40 or 50 — after reproducing and nurturing the offspring to childbearing age. We have already extended the average human lifespan two to three times more than it was back in the Stone Age and for millions of years before that, and we have adjusted quite nicely to the new reality.

Morally and ethically, in terms of how the advent of extreme life-extension would impact society is certainly a valid concern. It could get very messy for a while. John Wyndham wrote about it back in the 1950s in “Trouble With Lichen”. But longer term, assuming we eventually solve most of the serious problems that plague our society, I don’t think there is much question that we will successfully adapt to an indefinite lifespan and I have no doubt that we will want to do it.

I am somewhat of an advocate of such world ships that could carry a population equal to the current global population wherein upon arriving at other galaxy super clusters, the world ships would send colonizing teams throughout the galaxy cluster, and things could jump start from there.

It’s an intriguing possibility, but I always have to wonder if such a task would not be better suited to smaller vessels run by AIs and “manned” by either the seeds of a human population (embryos, or eggs and sperm) or even just DNA copies of a human population that can be reconstituted into a viable community upon arrival.

While I agree that extended lifespans goes hand in hand with interstellar exploration, I have to believe there are some limits. I’m not sure there will be many volunteers for undertaking a billion year journey, one which only their remotest descendants would ever see the culmination of. Heck, the odds are that whatever is living on the ship at the end of such a journey, it won’t even remotely resemble those who began it, even given the glacial pace of evolution!

Athena Andreadis, by the time we are able to build and power a ship big enough to house a couple of 100 or a 1000 people, then I’m guessing that the “problems” with shielding and procreation in space will have been licked. My angst is only with the pursuit of eternal life.

Apart from the lack of engineering and science, which prevents us from building such ships, it is also the lack of collective will to build such a ship. Culturally we are not there – for better or worse.

The reason for building ships capable of traveling to the stars, for me, is obvious. We need to be in more places than just Earth, to make sure we are able to withstand catastrophic disasters. Having said that, we have only known our predicament for a relatively short period of time and in the future we will procede with such an enormous (and important) undertaking.

Tesh, I wrote extensively about large-scale crewed space traveling (and the need for it) in my Making Aliens six-part series which starts here.

Tacitus, you hit the nail on the head: uploading will make a clone or a copy. The uploaded identity will start diverging from the original the moment it gains consciousness and the original will still experience the process of dying. This is what I mean by saying that a mind is inseparable from the brain; this concept is identical in meaning to your sentence “the mind is an artifact of the brain, nothing more.” And, I should add, nothing less. This intrinsic cannot be overcome by technology, no matter how advanced — but it can be finessed by far gentler methods. My second, upcoming article for H+ magazine will focus on this issue.

I know personally some of the pioneers who invested the whole stem cell field (Michael West being one of them) and they believe that much of what I have written previously is possible. Enough that they are putting their own money (and careers) on the line to make it happen. These are people with every bit the experience that you have. I am not just pulling this stuff out of my ass.

I will also tell you that these people are investing their own money into this stuff. People who bet their own money have far more motivation to succeed (and therefor will work much harder) than those who do not.

Athena, so really your objections are more definitional than biological/technological? If I am reading you right, you accept that it might be possible one day in the distant future to clone/copy/download a mind, but you don’t agree that this would constitute a true form of life-extension. If so, than I think we are pretty much in agreement to that point.

Now, I believe there are solutions that would be acceptable as workarounds to the problem of identity. We have already begun to use devices (like brain pacemakers) to replace essential brain functions, albeit on a very crude level. Most are peripheral devices today, but given enough time (and lots of it) I expect we will see the expanding role of technology in augmenting and replacing natural brain function.

So, jumping a few centuries into the future (perhaps), I foresee a time when implants will be able to take over major brain function in situ, and then perhaps, over a period of a few weeks or months, the implants can gradually take over the functional responsibilities with little or no discernible difference noticed by the subject. As you transfer control, you simply turn off the parts of the biological brain that have no further function, and thus you avoid the awkward dual identity problem.

An alternative and perhaps more desirable technique would be to use nanotechnology to directly replace neurons with something more durable (perhaps a version of that magic molecule, the carbon nanotube). Cell replacement already happens every moment of our lives, and so gradual replacement of brain cells with nanomachines of some kind would present no problem at all from an identity standpoint.

You are still left with what impact such drastic changes would have on the individual involved, but if you look at the types of drastic changes many people already successfully negotiate, from amputated limbs to debilitating strokes, I am not willing to underestimate the powers of human adaptation to reconcile with what could be a drastically new situation.

Interestingly enough, I am in the middle of writing a short story exploring some of these themes of brain copies and identity, and even touch on hibernation too! It takes place in the middle of “The Interregnum”, a future time when a grand bargain is made between the inhabitants of a ravaged Earth to go into mass hibernation and let the Earth lie fallow to give it time to recover in exchange for better, healthier and greatly extended lives when they are revived. (I’m not a published writer but I do have a novel (fantasy) on the go, currently in its third draft.) Not sure what I will do with it when it’s done, but if it’s any good you might get a chance to read it somewhere sometime :-)

Kurt9, you shift the goalposts each time you post. Until your latest, you were arguing for cryonics. Now you suddenly introduce stem cells. Stem cells are a completely different ball game. I won’t discuss them further here because, as I said in my previous entry, I will be doing so in my next article for H+ magazine. We can talk about stem cells after the article appears — if Paul marshals the stamina to repeat this experiment!

Regarding cryonics, let Alcor or any company in that domain freeze something that resembles a human in size and metabolism (say, a young bear) for a few years with their latest technology, then resurrect it. Not cells, not brain slices, not a mouse, not a dog, all of which differ in crucial ways. A bear would still be easier than a human, since bears go through quasi-hibernation. And they won’t have to worry about language or the capacity to discuss platonic ideals or FTL travel. I guarantee you that if this were to happen, the people who did it would shout it to the rooftops. So where is this triumphant announcement?

Tacitus — I also think we are in general agreement. My working definition of identity is self-aware continuity of consciousness. A clone/copy will be a real person/ality, but a distinct one — as twins or cloned animals are now. I consider renewal of the brain by organic replacement as possible but more complicated than you do, for reasons (rewind tape!) that I will go into in my next article in H+ magazine. Hmmm, I’d better not drop dead before this article gets published, or there will be lots of half-finished conversations!

I have published short fantasy and SF fiction myself, and have five SF novels at various stages of completion or revision (the published works and excerpts of the unpublished ones are at the stories section of my site). So I’ll be very interested to see your efforts when you deem them ready for the world!

Regarding live extension, there is a problem — and the following is not meant as a joke. If you wish live extension being available generally — what else –, then this implies, that you wish all *bad* people — and there *are* bad people — being around for a long time too.

Your personal enemy from school, college, or business will have very much time, and this person will do what? Above that think about people like Hitler, Stalin, or Pol Pot. If so many participants of the Centauri Dreams discussions think, that so many things will be possible, then why not a future super villain. If things go bad, one future day you will be surprized, that one of those beings has entered the same spaceship together with you and several thousand other persons, and you will be on an inescapable journey for several hundred years.

James M. Essig: ” I strongly feel that the book of FTL travel is far from closed.”

I hope so, because I like science fiction literature very much (as I have said before), and it looks like it is rather difficult — and for many authors impossible(?) — to develop an enjoyable dramatic composition, if journeys last very very long. There are exceptions, e.g. several stories by Charles Stross, if I remember correctly. And remember the classic Odyssee ;-)

Duncan, your point is among those that I brought up in the article I just sent to H+ magazine. Everyone thinks of themselves and those they like when they contemplate eternal life. Leaving aside major baddies, what about obnoxious in-laws or the department chair that demands honorary authorship? Frustration killings will skyrocket, if starvation doesn’t get us first!

As for FTL travel, it need not disappear from science fiction. Literary devices are one thing, feasible science another — though they constantly influence and inform each other.

In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For the last twelve years, this site coordinated its efforts with the Tau Zero Foundation. It now serves as an independent forum for deep space news and ideas. In the logo above, the leftmost star is Alpha Centauri, a triple system closer than any other star, and a primary target for early interstellar probes. To its right is Beta Centauri (not a part of the Alpha Centauri system), with Beta, Gamma, Delta and Epsilon Crucis, stars in the Southern Cross, visible at the far right (image: Marco Lorenzi).

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